Field
The present disclosure generally relates to makeup tools and, more specifically, to methods and apparatus for achieving target torque in tubular makeup.
Description of the Related Art
Construction of oil or gas wells usually requires making long tubular strings that make up casing, risers, drill pipe or other tubing. Due to the length of these strings, sections or stands of tubulars are progressively added to or removed from the tubular strings as they are lowered or raised from a drilling platform.
The tubular strings are formed by connecting a plurality of tubulars by fluid-tight threaded joints. Each fluid-tight threaded joint is formed by making up two tubulars with a threaded connection at a target torque.
A tong assembly is commonly used to make up or break out joints in the tubular strings. Typically, a tong assembly may be manually controlled by an operator during makeup. A dump valve is usually used to stop the rotation when a at a target torque. Depending on parameters of the tubulars, this manual control may lead to over torque, for example, when the rotational speed of the tong assembly is too high at a final stage of joint make up. Another approach to achieve the target torque is using a closed-loop control of torque or rotational speed during makeup. However, depending on the set speed, the closed-loop control method takes a long time to makeup each joint. Another approach to achieve the target torque is to rotate the tong assembly for a predetermined time at a constant speed. The predetermined time is obtained from heuristically measured values, which are results of particular parameters, such as the reactions time of the tong assembly to a specific type of tubulars and the speed of the tong assembly.
Therefore, there is a need for improved methods for achieving target torques during tubular makeup.